Anchor block supporting lever



April 6, 1946. R. s. OWEKNS 2,398,717

ANCHOR BLOCK SUPPORTING LEVER Filed March 1, 1945 l-NVENTOR RUs E \iOWENS w I Q BY W ATTOR Y Patented Apr. 16, 1946 ANCHOR BLOCK SUPPORTING LEVER Russell S. Owens, St. Louis, Mo., assignortoxWagnor Electric Corporation, St. Louis, Mo., a cor,- poration of Delaware Application March 1, 1945, Serial No. 580,407

12 Claims.

This invention relates to brakes for self-propelled vehicles and in its more specific aspects is directed to an improved self-centering mechanism for the shoe elements of the brake.

One of the objects of the invention is to provide the supporting means of an anchor block for a self-centering brake in the form of a spring in order to produce the necessary resiliency therein to generate the desired friction between the brake shoe and anchor block, thereby elimimating the need of an additional spring for thepurpose.

Another object of the invention is to produce a resilient linkage mechanism connecting the anchor pin and the cooperating ends of the brake shoe in which the resilient elements are incorporated into the linkage per se.

A further object of the invention is to provide a spring linkage connecting the anchor, pin and the shoe whereby the anchor block and the cooperating shoe end are maintained in constant frictional engagement. v

A still further object of the invention is to provide in a brake assembly, a spring type connection between the anchor pin and the shoe to maintain the anchor block associated with the pin in frictional engagement with the cooperat ing end of the shoe in order that when the shoe' moves relatively to the anchor block, the spring elements will maintain the adjustment by firm frictional engagement of the parts.

Other and further objects 'of the invention will occur to those skilled in the arts to which this application pertains as the description proceeds, which, taken in connection with the accompanying drawing sets forth a preferred embodiment of the invention and selected modifications thereof but such disclosures are-not to be construed as a limitation of the invention which is limited only by the appended claims, and any and all modifications, alterations and variations of structure coming within the spirit and scope thereof are deemed to be included herein.

In the drawing:

Figure 1 shows an elevational view of the preferred embodiment of the invention;

Figure 2 shows a general perspective view of the linkage; v

Figure 3 is a sectional view-taken along the line 3-3 of Figure 1;

Figure 4 shows a modified construction of the anchor block mounting;

Figure 5 is a sectional viewtaken along line 5-5 of Figure 4; and

Figure 6 shows a plan View of another modified the form, partly in section, to show structural details.

Various expedients, have been employed in the brake art to eifect a centering of the brake shoes with respect to the brake drum in which said shoes operate. One of these expedients has been to shift the heel end of. the shoe with respect to the anchor pin, one form of which construction is disclosed in Reissue Patent No. 22,515. In brakes of the self-centering type it is desirable to produce sufficient- .friction between the sliding surfaces of the centering device to hold the shoe in centered position when thebrake is'released. The instant invention is an improved mean for doing this over the disclosure set forth in the identified patent.

The aboveobiects are achieved in the structure shown in the accompanying drawing in which held therein;

l is a conventional backing plate provided with an anchor pin 2. Fitted over the anchor pin 2 is an anchor block 3 disposed within a U-shaped block supporting element 4 secured to shoe 5 by means of a pin 6 which extends through the web of shoe 5 and through the legs of the U-shaped element 4. The pin 6 isfixed in the Web of shoe -5 and is enlarged as at T'- in order to be firmly The aperture in each of the leg elements 8 and 9is preferably 'in the form of slots l6 and II to" allow ready assembly of the U-shaped element 4 thereon and relative movement of shoe 5 and element 4. l V t The anchorblock 3 fitted over anchor pin 2 hasa curved surface 12 cooperating with a correspondingly curved surface l3 formed on the web porti'onof shoe 5. The radius of rotation is about the center of pin 6 such that the two surfaces may move relatively of each other about a common centerto thereby cause shoe 5 to adjust itself with respect to the axis of rotation of brake drum 25.

If, at the initial installation of the brake or at any time during the operation of the brake by cylinder 15, the outer surface radius of the brake lining does not concentrically engage the inner corresponding engagement surface of the brake drum, .a slippage will occur between shoe 5 and anchor block 3 which will allow the shoe to correctly center itself within the drum. The slippage of surface l2 onsurface-w about 6 as a center will cause the shoes to center themselves and thereby; again uniformly distribute the brake pressure over the engagement surface of drum 25.

Spring l6 retracts shoe 5 from drum 25 following each operation. e The. leg elements 8 and 9- are bowed, as shown manner to provide elasticity or stretchability, and

may be heat treated if necessary to increase the allowable stressability of the material used. These legs are then stretched in assembly, due to proper dimensioning of parts, a suflicient amount to cause them to act as tension springs between pin 6 and back surface of block 3. The spring action thus acquired tends to pull shoe and. block 3 together and causes surfaces l2 and I3 to bear heavily against each other. The leg elements 8 and 9 are indented as at IT and I8 to grip the web portion of shoe 5 and keep the same centered with respect to the anchorblock 3.. A retainin element I9 is provided to keep the anchor block and U-shaped element 4 fixed to the anchor pin 2. A modification of the above is shown in Figures 4 and 5 in which the same anchor pin 2, backing plate I, brake drum 25 and shoe 5 construction is employed. The pin 6 is the same as in the previously described construction. In this modifieation the U-shaped element 20, while being of different shape as previously set forth, has legs 2| and 22 which are associated with the anchor pin and shoe 5 in the same manner as also previously discussed. In this modification the leg elements, instead of being bowed as more, particularly shown in Figure 3, are crimped asat 23 and 24, which erimpings are treated in the same manner as parts 8 and 9 in order to impart spring qualities thereto. The same indentations l1 and I8 are formed in leg elements 2| and 22 for the same purpose asset forth above. The operation of the disclosure in Figures 4 and 5 is identical 7 to that set forth above. V

The operation of each of the devices depends upon the relative movement that takes place between anchor block 3 and the cooperating end of shoe 5 to cause relative motion between the two whenever wear occurs on the brake lining M or either end of the shoe engages the drum prior to the other end. The rotation about pin 6 takes place in both directions of movement, that is,

toward and away from the brake drum in order that the spacing between the shoe and the brake drum will be uniform to cause uniform pressure and wear on the friction lining.

The anchor block holder is assembled on shoe 5 by first slipping the ends of pin 6 through slots I0 and II and then forcing'the block 3 over the end of shoe 5, thereby bringing surfaces l2 and I3 into engagement and stretching parts 8, 9, 23, and 24 to frictionally engage surfaces l2 and I3.

Figure 6 shows another modification in which shoe 5' has a pin 6 fixed in the web of the shoe.

A U-shaped element 26 is provided having anchor block 3 and curved shoe end 28 received therein, all fitting over'anchor pin 2 as set forth above. The leg elements 21 and 29 of part 26 are slotted in the same manner as set forth above to fit over pin 6. The spring element is formed in back 33 of part 26by bowing same as shown and providing it with an indentation at 3| to keep block 3 and part 26 together in a locked condition.

Having fully described my invention, that which I claim as novel and desire to protect by Letters Patent of the United States is:

1. In a brake, a backing plate; a, brake shoe; a pivot pin fixed to said backing plate; an anchor block on said pivot pin; a U-shaped member receiving said anchorblock fitted over said anchor pin; means in said shoe adapted to receive the free ends of said U-shaped element, saidshoe having a curved end with a radius drawn about block and shoe to be drawn into engagement with each other, the legs on said U-shaped member being indented in order to center the shoe with respect to said anchor block; means to rotate said shoe about said'pivot; and said shoe when pivoting about said means centering said shoe with respect to the brake drum engaged thereby.

2. In a brake, a backing plate; an anchor pin secured'thereto; a U-shaped member; an anchor block received in said U-shaped member, said U-shaped member and anchor block having apertures therein to receive said pin; means in said shoe to pivot said shoe with respect to said U- shaped member, said U-shaped member having indentations therein to center said shoe with respect to said anchor block, said shoe having its end formedon a. radius about said means, said anchor block having a surface formed thereon complemental to the end of the shoe; and said U-shaped member having its legs resiliently formed in order to cause said complemental suri aces to firmly frictionally engage each other,'said shoe pivoting about said means in order to center saidshoe with respect to said backing plate.

3. In a brake, a backing plate; an anchor pin fixed in said plate; a brake shoe; means to pivot said shoe about said pin; means to enable said shoe to pivot about said pin which includes an anchor block; a U-shaped member receiving said anchor block and arranged on said pivot pin; a

second pivot pin secured in said shoe receiving the free ends of said U-shaped member; said means in said U-shaped member centering said shoe with respectto said anchor block, said shoe having its end curved on the radius about said second pivot, said anchor block having a surface complemental to said curved surface on said shoe; and said U-shaped member having its legs formed into a resilient bow to cause said complemental surfaces to frictionally engage each other but permit movement of said anchor block relative to said shoe about said second pivot as an axis to center said shoe with respect to said backing plate.

4. In a brake, a backing plate; a brake drum rotatable with respect thereto; a brake shoe pivotally mounted on said backing plate; means to pivot said shoe about said pin; means to connect said shoe to said pin which includes an anchor block and a U-shaped member to receive said anchor block receivable on said pin; means to pivot said shoe with respect to said anchor block, said shoe having a curved surface thereon drawn about said means, said anchor block having a curved surface complemental to said first mentioned curved surface, said Ushaped member having its legs bowed constituting same as springs to urge said curvedsurfaces into frictional engagement; and said shoe when pivoting about said means centering said shoe with respect to said drum.

5. In a brake, a backing plate; a drum rotatable with respect thereto; an anchor pin secured to said backing plate; a brake shoe; means connecting said shoe and said pin to pivot said shoe with respect to said pin which includes an anchor block; a U-shaped member receiving said anchor block and fitted over'said pin; means to secure said U-shaped' member to said shoe, said shoe having its oneend curved in a radius about said means, said anchor block having a surface complemental to said first mentioned surface; means to pivot said shoe about said pin; the legs of said U-shaped member being made into a spring in order to urge said surfaces into frictional engagement; and said surfaces moving relatively to each other about said means as an axis in order to center said shoe with respect to said drum.

6. In a brake, a backing plate; a brake drum;

an anchor pin fixed in said backing plate; a

brake shoe pivoted about said anchor pin; means to pivot said shoe about said anchor pin; means to connect said anchor pin in said shoe which includes an anchor block; a, U-shaped member, said anchor block received in said U-shaped member and having apertures therein receivable over said anchor pin: and pivot means in said shoe to receive the legs of said U-shaped member and said legs of said U-shaped member being deformed and made into a spring in order to urge said shoe into engagement with said anchor block, said anchor block and said shoe having complemental curved surfaces drawn about said last mentioned means as a center, said shoe pivoting about said means when being centered with respect to said brake drum by causing said complemental surfaces to slide one with respect to the other, said spring elements maintaining the adjusted position of said complemental surfaces whenever said shoe piv ts with respect to said anchor block.

7. In a brake, a backing plate; an anchor pin secured thereto; a U-shaped member; an anchor block received in said U-shaped member, said U-shaped member and anchor block having apertures therein to receive said pin; means in said shoe to pivot said shoe with respect to said U-shaped member, said shoe having its end formed on a radius about said means, said anchor block having a surface formed thereon complemental to the end of the shoe; and said U-shaped member having its legs deformed to make them resilient in order to cause said complemental surfaces to firmly frictionally engage each other, said shoe pivoting about said means in order to center said shoe with respect to said backing plate.

8. In a brake, a backing plate; an anchor pin secured thereto; a U-shaped member; an anchor block received in said U-shaped member, said U-shaped member and anchor block having apertures therein to receive said pin; means in said shoe to pivot said shoe with respect to said U-shaped member, said U-shaped member hav- 1 ing indentations therein to center said shoe with respect to said anchor block, said shoe having its end formed on a radius about said means, said anchor block having a surface formed thereon complemental to the end of the shoe; and said U-shaped member having a portion thereof deformed and made resilient in order to cause said complemental surfaces to firmly frictionally engage each other, said shoe pivoting about said means in order to center said shoe with respect to said backing plate.

9. In a brake, a backing plate; an anchor pin fixed in said plate; a brake shoe; means to pivot said shoe about said pin; means to enable said shoe to pivot about said pin which includes an anchor block; a U-shaped member receiving said anchor block and arranged on said pivot pin; a

second pivot pin secured in said shoe receiving the free ends of said U-shaped member; said means in said U-shaped member centering said shoe with respect to said anchor block, said shoe having its end curved on the radius about said second pivot, said anchor block having a surface complemental to said curved surface on said shoe; and said U-shaped member having a portion thereof deformed and made resilient to cause said complemental surfaces to frictionally engage each other but permit movement of said anchor block relative to said shoe about said second pivot as an axis to center said shoe with respect to said backing plate.

10. In a brake, a backing plate; a brake drum rotatable with respect thereto; a brake shoe pivotally mounted on said backing plate; means to pivot said shoe about said pin; means to connect said shoe to said pin which includes an anchor block and a U-shaped member to receive said anchor block receivable on said pin; means to pivot said shoe with respect to said anchor block, said shoe having a curved surface thereon drawn about said means, said anchor block having a curved surface complemental to said first mentioned curved surface, said U-shaped member having a portion of its structure deformed and made into a spring to urge said curved surfaces into frictional engagement; and said shoe when pivoting about said means centering said shoe with respect to said drum.

11. In a brake, a backing plate; a drum rotatable with respect thereto; an anchor pin secured to said backing plate; a brake shoe; means connecting said shoe and said pin to pivot said shoe with respect to said pin which includes an anchor block; a U-shaped member receiving said anchor block and fitted over said pin; means to secure said U-shaped member to said shoe, said shoe having one end curved in a radius about said means, said anchor block having a surface complemental to said first mentioned surface; means to pivot said shoe about said pin; a portion of said U-shaped member being deformed and made into a spring in order to urge said surfaces into frictional engagement; and said surfaces moving relatively to each other about said means as an axis in order to center said shoe with respect to said drum.

12. In a brake, a backing plate; a brake drum; an anchor pin fixed in said backing plate; a brake shoe pivoted about said anchorpin; means to pivot said shoe about said anchor pin; means-to connect said anchor pin in said shoe which includes an anchor block; a U-shaped member, said anchor block received in said U-shaped member and having apertures therein receivable over said anchor pin; and pivot means in said shoe to receive the legs of said U-shaped member and a portion of said U-shaped member being deformed and made into a spring in order to urge said shoe into engagement with said anchor block, said anchor block and said shoe having complemental curved surfaces drawn about said last mentioned means as a center, said shoe pivoting about said means when being centered with respect to said brake drum by causing said complemental surfaces to slide one with respectto the other, said spring elements maintaining the adjusted position of said complemental surfaces whenever said shoe pivots with respect to said anchor block.

RUSSELL S. OWENS. 

